Talk:All About "blue-green algae"/@comment-38.112.107.50-20100922154608
This from Nina who writes a regular article at Cambrian College "Green Friday" in an effort to make the college community more aware of environmental issues - this article is of interest to us! ________________________________ Summer is over, but most of us enjoyed some time out on the local lakes swimming, boating, fishing or just enjoying a coffee on the dock. Those of us that have been doing these things for awhile have been noticing big changes in our surrounding waters. What’s Happening to our Lakes and Rivers?? Really Low Water Levels After a winter of not-much-snow, water levels in most lakes were down this spring. Hot and dry weather continued throughout the summer and lake levels dropped even further mostly due to increased evaporation. Climate scientists point out that increased evaporation, resulting in lower lake levels, is consistent with many climate change projections. Our current low water levels point out how sensitive water bodies are to climate change and we can only image future water levels if dry winters and hot summers become more common. Low water levels have a profound effect on local ecosystems. Aquatic habitats change, or dry-up, resulting in changes to food webs and changes in fish species. From an economical point of view, less power is available from hydro-electric sources, sports fishing and tourism become less popular and ships must carry reduced loads on the Great Lakes. Blue-Green Algae Blue-green algae are naturally occurring microscopic plants found in all aquatic environments. Blue-green algae aren’t usually a health threat but, in nutrient-rich, warm waters, they can “bloom” and then their population increases exponentially, releasing toxins into the water. At this point the algae bloom appears as a scum on the surface of the water. Warm water temperatures in July and August combined with nutrients from detergents, fertilizers, and sewage can cause a blue-green algae bloom – something that is becoming a more common phenomenon in our area. Cottagers and homeowners living on lakes need to be aware of maintaining a more natural shoreline and make sure that they are not discharging sewage or grey water into the lake. Blue-green algae blooms may be starting to be a problem here but in Manitoba they are already a huge environmental problem. Visible from space, are the massive blue-green algae blooms of Lake Winnipeg, the 10th-largest freshwater lake in the world. Although Lake Winnipeg is isolated from major urban centers, the major contributing factor to Lake Winnipeg's problems comes from agricultural run-off. More than 100,000 farms surround the Lake Winnipeg basin contributing to the increased nutrient content of the lake. Kind of makes a strong case for choosing more local, organically-grown foods, eh? Closed Beaches In the districts of Sudbury and Manitoulin, there are 35 designated beaches that are tested for bacteria throughout the summer. Unacceptably high levels of bacteria may be a risk to swimmers health and this summer a few beaches were closed due to high levels of unhealthy bacteria. The public health laboratory analyzes water samples from each of the 35 beaches for Escherichia coli (E.coli) bacteria - an “indicator of fecal pollution”. Fecal pollution comes from sewage and/or animal droppings. Sources of this type of pollution include, agricultural run-off, overflows from sewers, and from animals and birds. Each of us can control many sources of fecal pollution. You can maintain your own sewage system, abide by “poop and scoop” laws, and reduce household water use which in turn, will help avoid overflow problems at the municipal sewage treatment plants that may cause untreated sewage to enter lakes and rivers. At this time, it is NOT illegal for sewage treatment plants to dump excessive sewage into our waterways.